Volume Phase Transition in Interpenetrating Networks of Poly(<i>N</i>-isopropylacrylamide) with Gelatin

Dhara, Dibakar; Rathna, and G. V. N.; Chatterji, P. R.

doi:10.1021/la990065j

Cited by 42 publications

(41 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…31 Special morphologies for pNIPAM-based thermoresponsive materials such as hydrogel nanoparticles, 32 poly(l-lactic acid) microcapsules as a pNIPAM gel container, 33,34 shell-crosslinked vesicles, 35 and an interpenetrating network with gelatin 36 were studied. These types of phase transition polymers are preferentially investigated for applications in biology and medicine for use in drug delivery systems, 1,13,32,33,35 carriers for gene delivery, 3 thermosensitive superabsorbents, 2 determination of enzyme concentrations, 16 and control of enzymatic activity.…”

Section: Introductionmentioning

confidence: 99%

Synthesis and properties of new thermosensitive polymer systems

Bohrisch

Hahn

Maedler

et al. 2007

J of Applied Polymer Sci

View full text Add to dashboard Cite

The controlled thermal release of aqueous solvent mixtures from polymeric gel particles was investigated. A new type of a polymeric gel consisting of a maleic anhydride/poly(ethylene glycol) condensation product as a crosslinking macromonomer and acrylamides was synthesized by solution or inverse emulsion polymerization for the investigation. Afterward a shell of crosslinked polystyrene was coated to stabilize this new kind of "microcontainer" for the application. This concept was shown as generally useful for various mixtures of organic solvents and water. The cloud point temperature of the polymer gel strongly depended on the following parameters: the type and content of organic cosolvent, the degree of polymerization and constituents of the polyester moiety, and the type and content of the comonomers

show abstract

Section: Introductionmentioning

confidence: 99%

Synthesis and properties of new thermosensitive polymer systems

Bohrisch

Hahn

Maedler

et al. 2007

J of Applied Polymer Sci

View full text Add to dashboard Cite

show abstract

“…3b). [15,16] Although the PNIPAm gel showed a drastic deswelling at 35±40 C due to its lower critical solution temperature (LCST), the L 3 -PNIPAm gels showed only a slight deswelling at increased temperatures due to the existence of L 3 ceramic structures. Moreover, the large porosity values obtained from BET measurements on the L 3 -PNIPAm gel with 95 wt.-% water content is because of the swelling induced by the water-rich environment of the sparse, interconnected, polymer (PNIPAm) structure.…”

mentioning

confidence: 99%

Bicontinuous, Thermoresponsive, L₃‐Phase Silica Nanocomposites and Their Smart Drug‐Delivery Applications

et al. 2005

View full text Add to dashboard Cite

The discovery that ordered nanoporous materials can be produced using a surfactant-templated approach has opened up a new era in the synthesis of ordered nanoscale materials.[1±4] Many investigations have explored the preparation of nanoporous materials with novel chemical composition, [5] the fundamental nature of the reaction processes, [6±8] and potential applications, such as catalysis [9±11] and separation technology, [12,13] which is expected to open up further application possibilities. Interest in the structure of the pore network is necessarily concomitant with the formation of different structures, including hexagonal, cubic, and lamellar structures. The liquid-crystal templating approach to these structures is based on a micellar or tubular structure. After templating, the inorganic precursor condenses to form a rigid cast of the underlying liquid crystal, and the organic phase can be removed to leave an inorganic solid composed of a periodic nanoporous structure with uniform diameter and distribution. Although the feasibility of choosing the pore size offers a wide range of possibilities for hosting different molecules, reports on the drug-delivery behavior of ordered nanoporous materials are not abundant and usually involve structural modification. [6] In particular, a systematic drug-delivery study on the porous geometrical shapes of nanoporous materials has yet not been reported.Here we report the smart drug-delivery application of synthesized L 3 -phase (sponge-phase) nanoporous materials in highly controlled drug release, upon integration of a thermoresponsive polymer, poly(N-isopropylacryl amide) (PNIPAm). The L 3 phase is formed by the self-assembly of amphiphilic templates during the formation of nanoporous inorganic materials, and it consists of a three-dimensional random packing of a multiply connected bilayer of the surfactant and cosurfactant that divides the space into two subspaces filled with solvent, based on the liposome structure. The pore size and the distance between the silicate layers in the porous structure were controlled by changing the hydrophilic domain, for example, by varying the amount of water. The aim of this work is to explore a new potential application of the bicontinuous, disordered, L 3 -phase nanoporous structure and its capability of acting as a convenient reservoir for controlled drug release. For this purpose, we introduced indomethacin (IMC), an antipyretic and analgesic drug, into the non-calcined, silicified L 3 gels and L 3 -integrated thermosensitive PNIPAm polymer gels (L 3 -PNIPAm), and subsequently demonstrated the in-vitro drug-release process by a step-wise temperature change.The synthesis of silicified L 3 gels was achieved using a method that was a slight modification of one previously reported, [14] in which the order of mixing of the three components of the L 3 phase was not important, but it was necessary to maintain the correct ratio of hexanol to the surfactant, 1-hexadecyl pyridinium chloride (CPCl), in order to ensure phase purity and stabi...

show abstract

“…The water content was calculated as (W w Ϫ W d )/W w . 6 To test water retention, specimens, 500 mg for each sample, were evenly seeded on petri dishes (50 ϫ 11 mm; Fisher Scientific, Pittsburgh, PA) and 10.0 g of D.I. water was added.…”

Section: Water Content and Retentionmentioning

confidence: 99%

Pectin and polyacrylamide composite hydrogels: Effect of pectin on structural and dynamic mechanical properties

Liu

Cooke

Coffin

et al. 2004

J of Applied Polymer Sci

View full text Add to dashboard Cite

Composite hydrogels of pectin and polyacrylamide were synthesized and evaluated by scanning electron microscopy, atomic force microscopy, light microscopy, and dynamic mechanical analysis. The crosslinking polymerization of acrylamide in pectin solution resulted in a composite having a macroporous pectin domain with an interstitial polyacrylamide domain. This composite had improved mechanical properties compared to those of either polymer alone, and it absorbed and retained more water than crosslinked polyacrylamide alone. Furthermore, crosslinking polymerization of acrylamide in an existing pectinate scaffold resulted in a double-network architecture, where filamentous polyacrylamide networks penetrated through pores of the pectin scaffold. It was found that pectins dictated the features of microstructure in the composites through regulating the coordination of phase separation of the two components and water partition between the two phases. Results from this study highlight potential new uses of pectins in protecting the physical structure of environmentally sensitive polymers from mechanical damage related to freezing, lyophilization, and other conditions experienced during their use in biomedical and industrial products.

show abstract

Volume Phase Transition in Interpenetrating Networks of Poly(N-isopropylacrylamide) with Gelatin

Cited by 42 publications

References 51 publications

Synthesis and properties of new thermosensitive polymer systems

Synthesis and properties of new thermosensitive polymer systems

Bicontinuous, Thermoresponsive, L₃‐Phase Silica Nanocomposites and Their Smart Drug‐Delivery Applications

Pectin and polyacrylamide composite hydrogels: Effect of pectin on structural and dynamic mechanical properties

Contact Info

Product

Resources

About

Volume Phase Transition in Interpenetrating Networks of Poly(N-isopropylacrylamide) with Gelatin

Cited by 42 publications

References 51 publications

Synthesis and properties of new thermosensitive polymer systems

Synthesis and properties of new thermosensitive polymer systems

Bicontinuous, Thermoresponsive, L3‐Phase Silica Nanocomposites and Their Smart Drug‐Delivery Applications

Pectin and polyacrylamide composite hydrogels: Effect of pectin on structural and dynamic mechanical properties

Contact Info

Product

Resources

About

Bicontinuous, Thermoresponsive, L₃‐Phase Silica Nanocomposites and Their Smart Drug‐Delivery Applications